Pump



June 26, 1934. F, Hops'noN 1, 964,515

I PUMP Filed May 8. 195o s shets-sneet 1 @QS *QJ-www PUMP Filed May 8. 1930 3 Sheets-Sheet 2 June 25, 1934- F. G. HoDsDoN PUMP Filed May 8, 1930 3 Sheets-Sheet 3 Patented June 26, 1934 UNITE STATES PUMP Floyd G. Hodsdon, La Grange, Ill., assignor to International Harvester Company, a corporation of New Jersey Application May 8, 1930, Serial No. 450,660

6 Claims.

The invention generally relates to improvements in pumps, and more particularly to Vacuum pumps designed for use with milking machines.

The main object of the invention is to improve pumps of this class from the standpoints of operation and manufacture.

More speciiic objects are to provide a new arrangement of pump and vacuum can associated with the head of said pump; to provide renement in the crank case, cylinder and head of such a pump; and, to provide an improved, compact valve mechanism, thereby achieving a much desired low clearance volume for the pump.

Other objects will become apparent to those versed in this art as the disclosure is completed.

These very desirable objects are achieved by the construction herein to be illustrated and decribed, which construction represents one embodiment which the invention may assume in practice, by way of example.

In the drawings:

Figure 1 is a central, longitudinal sectional View of the pump and vacuum tank combination as seen along the line 1 1 appearing in Figure 3, as viewed in the direction of the arrows;

Figure 2 is a central, transverse, vertical, sectional view through the pump per se;

Figure 3 is a top plan view with the driving pulley for the pump shown in section;

Figure 4 is a top face view of a part of the valve plate assembly showing the spacer plate and the valves as they appear with the top valve plate removed, as seen along the line 4 4 appearing in Figure 6;

Figure 5 is a face view of the spacer plate per se;

Figure 6 is a central sectional view on an enlarged scale through the valve plate structure complete as would be seen when looking along the line 6 6 of Figure 4, or generally along the line 6 6 appearing in Figure 3;

Figure 7 is a similar sectional View showing only one of the valves as it appears along the section line 7 7, locking in the direction of the arrows appearing in Figure 4;

Figure 8 is a face view of one of the valve plates per se;

Figure 9 is a face View oi a valve ring;

Figure 10 is a transverse sectional view of this valve ring as appears along the line 10-10 in Figure 9; and,

Figures 11 and 12 are, respectively, top and side views of a crow-ioot spring used in the valve structure.

First of all in describing the structure in detail, it is to be understood that a sub-base l5 of any appropriate form is provided, it being intended that such sub-base be fastened securely to a solid foundation in a convenient location in the cow barn, as near as possible to the cows. One end of the base has made fast thereto in any convenient manner the crank case 16 comprising the pump. The lower end of the case 16 is provided with large, aligned side openings closed by bearing plates 17 bolted to the case to close said openings. Each plate is integrally formed with a bearing sleeve 18 which protrudes inwardly and transversely, the two sleeves being coaxially aligned, as best shown in Figure 2. Webs 19 connect the sleeves and plates to strengthen and truss the bearings thus formed for the drive shaft 20. One end of said shaft protrudes from the face of one plate so that a drive pulley 21 may be secured thereto, while the shaft opening in the opposite bearing plate is closed by a Welch plug 22. Between the inner ends of the bearing sleeves 18, which by the way are spaced apart, the shaft 2G has formed thereon an eccentric wheel 23 around which is loosely disposed an eccentric ring 24 held against endwise displacement from the wheel 23 by side members 25 provided for that purpose. The ring 24 has formed therewith a vertically extending connecting rod 26, which is connected in the usual way to the wrist pin 27 carried inside a piston 28.

The piston 28 is reciprocable within a cylinder liner or sleeve 29, which hangs from its rest on the open top of the crank case downwardly into the case, as shown in Figures 2 and 3, and spaced from the walls of the case to leave a breather space 30, as will later be made more clear. The bottom of the case 16 constitutes an oil sump which is supplied through the iiller elbow 31 and may be drained through any suitable plug, not shown, tted into the tapped opening 32 at the bottom of the case.

Secured by suitable cap screws to the top of the open crank case and on top oi the cylinder sleeve 29 is the improved head 33. An improved valve mechanism, generally shown in Figures 1 and 2, at 34 is clamped between the case and head as will later be more particularly described. The head, above the valves, is divided into an inlet chamber 35 and an exhaust chamber 36 by means of a depending, vertical, cross partition 37, there being an exhaust lead 38 fitted into the head to communicate with the said exhaust chamber 36. The inlet chamber 35 is in direct communication with a short narrow, closed passageway 39 formed in the head and leading to an enlarged circular head extension 40 having an annular flange 41 formed on its underside to receive and be closed by a vacuum can 42 having a. tight bottom 43, and side handles 44. The can, at its top, carries a flange ring 45 on its exterior, a gasket ring 46 being used as a seal between the ring 45 and flange 41. A vacuum pipe line connection 47 extends from the enlargement 40, as shown. The improved valve mechanisms 34 between the head and crank case top will now be described in detail. As shown in Figure 1, the can 42 when in position during operation of the pump occupies a position closely adjacent the pump and is arranged between horizontal planes passed through the top and bottom of the pump. This makes for a very desirable compactness. f l

Looking to Figures 4, 5, 6, 7 and 8, it will be seen that the Valve structure comprises threel sheet metal plates, to-wit, a lower, and a'n upper valve plate 48, each designated by the same reference character, as they are the same, andan intermediate spacer plate 49, there being suitable gaskets 50 provided between the plates and adjoining'parts, as best shown in Figure 6. The valve plates 48, as has been said are identical, and, as shown in Figure 8, they are circular and formed with a marginal ring of breather holes 51;. Each plate is divided into four quadrants, two of which, on one side of a diametric line, are eachformed with an inner and outer ring of port holes 52, while thetwo other quadrants on the other side of `the same diametric line are each provided with a single ring of port holes 53. Looking to Figure 5, it will be seen that the spacer plate has a half ring of marginal breather holes 54 and that the plate is also divided into four quadrants, each of which is formed with a large opening 55.

When the plates are superimposed in assembly, as shown on an exaggerated scale inFigure 6, it will be seen that the double ring of holes 52 inthe lower valve plate lare beneath the single ring of holes 53 in the'top valve plate on one side of a. diametric line. On the other side of the said Vline the reverse arrangement prevails, as the holes 52 are on top while the holes 53 are on the bottom.k Thisrelative ldisposition of the ports or holes results from the fact that Athe plates are offset angularly a distance of 180 degrees with respectsto each other. Thus, there will always be a half circle of breather holes 5l in the two valve` plates 48 in registry with the half ring of breather holes 54 of the spacer plate. Making the two valve plates ,the same with a complete ring of breather holes simplies manufacture for, if only half circles of breather holes were to be provided, obviously said plates would have to be formed one as a right and theother as a ,left. Theseregistering half rings o breather holes 51, 54 are all in registry furtherwith a half ring of breather Yholes ,56. leading throu'ghthe flanges ofthe cylinder sleeve 29 and crank case top, .as appearsfrom FiguresV l and to the breather space 30.*heretefo`re described.

.In the four large.holes .5.5 of the spacer plate 49,are. mounted fouryalves, two oiwhich are inlet valvesand the other two beingA outlet valves. As shown best in Figures 4 vandi, the outlet valves appear 4,at 57...(see`also Figures 9 and 10) the l Y same made ring-shape of thin spring sheet metal.

The inlet .valves appearat 58, and they are in 'all respects .identical in T'structure .with the outlet valves. The outlet valves 57, as shown in Figure .6,.seat against the, ports53A in the lower valve plate 48-` and are heldV downby the crow-foot springs 59 (see Figures 11 and 12), while the inlet valves 58 seat upwardly against the ports 53 in the upper valve plate 48 and are held up by inverted crow-foot springs 59. Each valve 57, 58 is provided with two pins 60, which slide up and down in two of the valve holes 53 (see Figure 7) and in that way they are kept in their proper positions. Each crow-foot spring at its center is similarly provided with a pin 6l which ts into a hole 62 at the center of the double ring of ports 52 in the valve plates 48. Thus, the crow-foot springs are held in such a position that their four arms hold the valve rings 57, 58 lightly to their seats. The entire valve plate assembly is additionally held together by a screw 63 passed through the plates centrally and up into the partition wall 37, as shown in Figures l and 2.

Any Vsuitable motor, such as an electric motor, (not shown) will be secured to the sub-base 15, said motor being belted to the pulley 21 of the pump to drivethe same.

Before starting the vacuuml pump in operation, the vacuum can 42 is resting on the sub-base l5 about a half an inch below the overhang of the cylinder head. In this manner there is no load l on the vacuum pump when it is started, which is quite important, since the pump is directly connected by a V-belt to the motor. When the pump comes up to speed, the vacuum tank is lifted upwardly by grasping the two handles thereof until the tank is held up by vacuum (or the outer atmospheric pressure) and sealed by the rubber ring between it and the cylinder head overhang.

In operation then on the up stroke of the piston,

thesame comes within 3 2 of an inch of the lower valve plate. plates, it is possible to geta very low clearance volume, and this is important from the standpoint of efliciency. The valve plates besides being clamped between the head and case by the cap screws shown are also held by the screw 63 to the partition wall 37, said wall dividing the head into two parts-'the vacuum side towards the Vacuum can, and the outlet side provided with the pipe outlet 38, which pipe in the usual milking machine installation will be led outside of the building or else some distance away in order to get rid of any oily vapor and to reduce the noise. During this part of the stroke, the outlet valves 57 have been closed, but now, as the piston goes upwardly, the inlet valves close and the breather holes and space around the cylinder liner i and goes into the crank case, and it also takes most of the oil that goes by the discharge valves back into the crank case.

The above cycle circulates the oil through the valves; makes them seal better; and, returns the oil back to the crank case. This gives better lubrication to the moving parts and economizes on oil. Also, by this means, the crank case acts as an expansion chamber and so equalizes the intermit- By using these sheet metal valve tent flow of air from the outlet valves into a sub- By making the valve plates, valves, and springs i of sheet metal stampings, the construction was simplified and costs are reduced. Obviously, eX- treme compactness also results. 'Ihere is no breathing outlet in the crank case to the outside air, as in conventional pumps, to take care of the expansion and contraction of air in the crank case due to the piston movement. This is provided for by the space 30 around the cylinder liner 29, which communicates with the bottom part of the crank case. Continuing, the piston now moves downwardly, drawing air out of the vacuum can, through the inlet chamber 35 and inlet valves 58, the air passing through the holes 53 of the top valve plate and around both the inner and outer circumferential edges of the valves 58, and thence through the double ring of holes 52 in the bottom valve plate to the piston chamber. The upper part of rivets or studs 60 of the valves 57, 58 is so proportioned that it may strike the upper valve plate on outlet valves and lower valve plate on inlet valves and thereby prevent the lower part of the stud from coming so far out of its hole as to permit the valve ring to slide sideways; also, these studs prevent the rings from sticking to either valve plates if the oil is heavy during low temperatures. A small amount of oil is also sucked up by the piston rings into the piston chamber because, even though the lower end of the cylinder block is almost closed up, there is a considerable splash of oil from the sump onto the cylinder sleeve walls. Also at this moment the air in the crank case is slightly compressed by the downward movement of the piston, but it escapes up between the cylinder sleeve and wall (space 30) and upwardly through the holes 56 and the holes 51, 54 around the edges of the plates 48, 49 into the outlet chamber 36 and through the discharge pipe 38.

The vacuum can or tank functions to supply an even vacuum for use in a pulsator of the milking machine, thereby insuring even pulsations. The can will also catch dirt particles and keep the same from getting into the pump valves. Also, if milk is drawn into the pipe line from an overflowing bucket, it will collect in the tank away from the pump, so that it can readily be seen and emptied out. Pipe line condensate will also be caught by the can.

Obviously, the valve mechanism of this invention could be adapted for use in air compressors.

From the above detailed disclosure it will now be clear that structure has been provided which achieves all of the desirable objects heretofore recited ior this invention. It is the intention to cover all changes and modications of the example here chosen for purposes of illustration as do not materially depart from the spirit and scope of the invention, which is indicated by the following claims.

What is claimed is:

l. A pump comprising a crank case open at one end, a cylinder liner inserted in said open end to leave a space between the liner and case, a head, flat valve plate mechanism between the liner and head, said head having a partition therein to divide the same into an inlet and exhaust chamber, means securing said iat valve plate mechanisrn to said partition, an inlet lead to the inlet chamber, an exhaust lead from the exhaust chamber, and securing means passed through the head, valve mechanism and liner to secure the parts to the crank case.

2. A pump comprising a crank case open at one end, a cylinder liner inserted in said open end to leave a space between the liner and case, a head, iiat valve plate mechanism between the liner and head, said head having a partition therein to divide the same into an inlet and exhaust chamber, means securing the center of said iiat valve plate mechanism to said partition, an inlet lead to the inlet chamber, an exhaust lead from the exhaust chamber, there being breather openings from said exhaust chamber leading to the crank case, and securing means connecting the head, periphery of the valve plate mechanism, and liner, to the crank case.

3. A pump comprising a crank case open at one end, a cylinder liner inserted into said open end and providing a breather space between the liner and case, a head connected to the case and provided with a cross partition wall to leave an inlet and an exhaust chamber, valve mechanism clamped between the case and head, means securing said valve mechanism to the partition wall, and a breather by-pass from the exhaust chamber to the breather space and crank case.

4. A vertical pump comprising a crank and cylinder case open at its top end, a head divided by a partition wall to form inlet and exhaust chambers closing said top end of the case, a flat plate valve supporting structure clamped between the head and top end ci the case, said head having a lateral horizontal extension comprising a narrow hollow passage-way portion from the inlet chamber, said extension at its outer end being circularly enlarged and presenting a relatively large open lower face, said open lower face adapted to be closed during operation of the pump by a cylindrical vacuum storage can, and a lead out of the top of said circularly enlarged portion of the extension.

5. A pump structure comprising a horizontal base, said pump structure embodying a vertically disposed crank case and cylinder body mounted on the base, said body at its upper end being open and having a head divided into inlet and exhaust chambers to close the same, said head having an elongated laterally disposed horizontal extension providedy with an enlarged opening on its under side which opening communicates through a passage with the inlet chamber in the head, and a vacuum can adapted to close said l2-0 opening in the extension and being in closing position only when the pump operates and produces vacuum, said can depending vertically from the extension alongside the crank case and cylinder body with its lower end disposed slightly above i the horizontal base.

6. A pump structure comprising a horizontal base, said pump structure embodying a vertically disposed crank case and cylinder body mounted on the base, said body at its upper end being i3() open and having a head divided into inlet and exhaust chambers to close the same, said head having an elongated laterally disposed horizontal extension provided with an enlarged opening on its under side which opening communicates 21.35 through a passage with the inletl chamber in the head, and a vacuum can adapted to close said opening in the extension and being in closing position only when the pump operates and produces vacuum, said can being vertically disposed and MO arranged closely beside the vertical crank case and cylinder body, the can and crank case and cylinder body lying between a horizontal plane passed through the extension and head and another horizontal plane passing through the top of WLS said horizontal base.

FLOYD G. HODSDON. 

